Innovative solution for offshore wind advances the energy transition

The Kriegers Flak Combined Grid Solution (CGS) demonstrates a significant step forward in the high-voltage direct current HVDC Light^® technology. This groundbreaking hybrid interconnection has now been in commercial operation for a year smoothly exchanging renewable energy between Denmark and Germany. Enabled by Hitachi Energy’s HVDC solution with its digital master controller system, Kriegers Flak integrates power from three offshore wind farms in the Baltic Sea. In the future, a total of four offshore wind farms – two each from the German and the Danish side – will be combined into the system.

The project was co-funded by the European Union (EU) to help secure a sustainable power supply to the region. Over the past year, the Kriegers Flak system has demonstrated how HVDC hybrid solutions can optimize power grids, and offer more sustainable, flexible, and secure applications for offshore wind, to support the EU’s 2050 climate neutrality targets. The hybrid HVDC Light system manages the complex task of controlling the entire Kriegers Flak CGS. By adjusting power flows in real-time, it integrates and supports the wind farms and the two asynchronous AC power grids in both countries – ensuring flexible and secure supply to European consumers.

The 400 MW HVDC converter station is the enabling technology for the interconnector, which is jointly owned and operated by transmission system operators Energinet of Denmark and 50Hertz of Germany. The interconnection can provide power to 600,000 households.

“We are delighted to be part of this innovative project, which shows how our leading technology solutions support the vision of an interconnected and Net Zero European energy system,” said Niklas Persson, Managing Director of Hitachi Energy’s Grid Integration business. “Together with Energinet and 50Hertz, we have shown how the integration of offshore wind power can be optimized to increase efficiency and reduce costs, enabling electricity to become the backbone of the energy system.”

“During the first year, the Kriegers Flak Combined Grid Solution has achieved the transport of offshore wind power and the provision of transmission capacity for cross-border electricity trading in a joint technical facility,” said Dr. Frank Golletz, Chief Technical Officer (CTO) at 50Hertz. “This is an important step for the future expansion of offshore wind energy use in the North and Baltic Seas.”

Henrik Riis, senior vice president, and CEO at electricity transmission, Energinet said, “The Kriegers Flak Combined Grid Solution combines offshore wind and interconnectors and is a leading example for future energy islands and an efficient and fast green transition.”